Filter element.



PATENTED MAY 12, 1908.

C. SELLENSGHEIDT. FILTER ELEMENT.

APPLICATION FILED JUNE 22,1907.

2 SHEETBSHEET l.

PATENTED MAY 12 G. SELLENSGHEIDT.

FILTER ELEMENT.

APPLIOATION FILED JUNE 22,1907.

2 SHEETS SHEET 2.

W a 2 2 Mn ventr:

CARL SELLENSGHEIDT, O-F BERLIN, GERMANY.

FILTER ELEMENT.

Specification ofLetters Patent.

Patented May 12, 1-908.

App'licationfiled June 22, 1907. Serial N0. 380,195.

To all whom it may concern:

Be it known that I, CARL SnLLENscHEmT, a subject of the German Emperor, and resident of Berlin, Germany, -have invented 'cer tain new and useful Improvements in Filter Elements, of which the following, taken in conjunction with the accompanying drawings, is a full, true, and concise specification.

Myinvention relates to filter elements for use in the well known forms of presses forfiltering liquids, and especially such liquids .as beer and wine, which contain carbonic acid; and the invention consists in the construction and relative arrangement of the parts of .a filter element, possessing the specialadvan- 'tage of being both inexpensive and entirely neutral to carbonic acid, and the further advantages of not requiring special packing to prevent leakage, of increased available filtering surface, and lightness and compactness, all as will be hereinafter more fully described and especially pointed out in the accompanying claims.

Referring to the drawings which form a part of this application, Figure 1 represents a main frame of a filter element constructed in accordance with my invention, and the detail views accompanying said figures are cross-sections of the side bars of the frame at the oints indicated respectively by the dotted ines; Fig. 2 is a plan view of a similar form having the filter grids formed as a separate part thereof; Fi 3 is an enlarged crosssection on the line lII-JII of Fig. 2; and Fig. 4 is a similar view on lines IVIV.

The filter element consists of a main gridsupporting frame a made of metal or other suitable rigid material given an exterior contour comformable to the style of filter press with which it is to be used In the style herein shown, the usual channel apertures d are formed in the diagonally opposite corners of the frame, these being for the inlet and outlet of the liquid in a manner which will be well understood by those familiar in this art, and a network 6 of tightly drawn wires is stretched across the frame for supporting its filtering medium.

The entire frame a is incased within a covering b of compressible elastic material which is-neutral to carbonic acid, such, for example, as ordinary rubber. The cross sections at various places show that the metal of the frame is everywhere incased. By thus encompassing the entire surface of the frame a, including even the channel apertures d, with the rubber, it will be observed that the filtered liquid does not come into contact with the metal or other material of the frame a .and that while adequately rigid, it isalso possible, by reason of its compressiblesurface, to be used in the press without employing in terposed packings or other instrumenta'lities for making tight joints. As the rubber on the interior wall of the frame a and on the two opposite sides thereof is virtually all that is employed for the above purposes, it willbe seen that the rubber on the outer wall .of the frame maybe omitted if desired, but for obvious reasons of durability and ease of pplication, I prefer to incase the entire fra e in the rubber, as above described.

Referring especially to Fig. 2, I exhibit'a filter element of special construction with the grid or supporting framework .for the filtering material formed as a separate part of the element. In this device the filtering grids consist each of an auxiliary frame f, from side to side of which are laid a plurality-of wires e in network form, as clearly indicated and under tension. The auxiliary frames f fit within the main frame a, being parallel with each other and spaced a suita le distance apart,-as shown in the drawings, and

the said auxiliary frames are united to the main frame by means of wire or wire clips h,.

as indicated by the black line in Fig. 3, which when tightened serve to bind the two frames together and further stretch the wire network. The rubber covering b is then molded or otherwise formed about both frames so that the marginal portions of the network grids are grasped and supported by it, the wires extending from out the rubber covering, as clearly shown in Figs. 3 and 4.

t will be seen from Fig. 4, moreover, that the liquid passage d which leads as usual from the channel aperture d through the frame and into the space between the grids, is also interiorly covered or lined with the rubber, so that none of the metal of either of the frames is exposed to the liquid. Pure drawn nickel wire is preferably used for the wire of the network. Other metals, however, can also be used, as the same when in the form of drawn wire are more impervious to the liquids spoken of on account of their harder surfaces. Still other substances capable of tension, such as gut string and the ike,'can be used -with equal effect. The stretched Wire network possesses a flexibility which is'highly advantageous in sustaining the pressure and shock when the li uid is passed through the filter, and has the rther advantage of permitting layers of filtering material to be employed, which are made of shorter fibers than could formerly be used and therefore of less thickness, Without impairing the thoroughness of the filtering process.

. In the above described forms of my invention it is to be observed that the wires'e are stretched or tautened in straight lines across the frame, forming a rectilinear lattice, each Wire being under longitudinal tension, which feature adapts the grids thus formed in a most effective manner to withstand the lateral pressure of the filtering medium.

Having thus described my invention, What I claim and desire to secure by United States Letters Patent, is:

1. A filter element comprising a frame and agrid therefor adapted to withstand the lateral pressure of the filtering material and formed of a rectilinear lattice or network of metallic wires under longitudinal tension.

2. A filter element comprising a main frame, and a grid therefor consisting of an auxiliary frame and a network of stretched wires thereon. i v 3. A filter element comprising a main frame and a grid therefor consisting of an and a coating auxiliary frame having a wire network thereacross and means for binding said auxiliary frame to the main frame.

4. In a filter element, a main frame and a filter grid therefor, in combination with a coating of elastic material like rubber, en compassing said frame and the marginal por tionof said filter 1d so as to support the latter in said main ame.

5. In a filter element, a'main frame and filter grids therefor consisting of two auxiliary frames having wire network across them or casing of material like rubber complete y encompassing said mainand auxiliary frames. v

6. In a filter element, a main rigid frame, a grid therefor consisting of an auxiliary frame adapted to fit Within said main frame and having Wires stretched from side 'to side thereof, incombination with means for binding said auxiliary frame within the main frame to further stretch said Wires and a rubber covering applied over said united frames. In testimony whereof, I have signed my name to the specification inthe presence of two subscribing witnesses.

CARL SELLENSOHEIDT. Witnesses HENRY HAsrER,

WOLDEMAR HAUPT. 

